Lawn-mower grinder



March 27, 1928,

P. A. ANDERSON LAWN MOWER GRINDER File'd May 8, 1925 Patented Mar. 27, 1928.

, NITED STA PHILIP A. ANDERSON,

y 0F ATLANTIC, IOWA.

@A1-Em form.

LAWN -MOWEB GRINDER.

ApplicationV filed ,May 8,

for lawn mowers improved meansfor secuing the Sharpener to the lawn mowerframe vso that the blades will be accurately sharpened. Y r e My invention consits in theconstruction, arrangement and combination of the :various parts of the device, whereby the objects contemplated are attained, ashereinafter more fully set forth, pointed out inv my claims, and illustrated i the accompanying drawings, in which: l

Figure; 1 is a front elevation of myimproved grinder' showing the manner In which itis attached to a'lawn mower.y

Figure 2is an lend elevation of thesame.l Figure 3 is an enlarged, detail, sectional view taken onthe line 3-3 of Figure 1.

- Figure t is an enlarged detail view showing the manner in which the device is attached to a lawn mower frame.

Figuref is a planview ot' a portion of the main frame showing in detail thev device Jfor guiding the cutter blade relative to the grinder, the grinder beingk omitted; and

Figure 6 is anend elevationl of same, the grinder beingishownv4 in v operative relation with the cutter blade. The numeral 10 indicates thesupporting trame of a lawn mower which is provided with the usual wheelslland a rotary cutter shaft 12, said shaft 12 being provided with helical cutter` blades 13,y only one of said blades, being illustrated. The lawn mower fra-me 10 is provided with side members 14C between whichthe ledgenplate and supportingrollers are mounted, said ledger` plate andsupporting roller being removed. The ledgerplate. is secured imposition by means of bolts `15, theV pivot members ofthe rollers being removed from thevbearings 16. Y

Y My improved device comprises a pair of supporting angles 17. vOlne of the members 17 is provided with Voutwardly extending v:trame members 18. The outerendrot each ot theimembers 1.84" isprovidedv with an up# 1925. ,serial No. 28,858. f

wardly extending portion 19, the upperl end o1 which is provided with an outwardly extending portion 20..4 rI`he other member 17 is provided with outwardly extending frame members 21, each having at itsk outer ends an upwardly extendingportion 22.

The members 19 and 22 are provided with Y vguide rods 23.which are` arranged parallel witheach other and spaced apart. One end ot the guide rods 23 is screw threaded and .providedwith nuts 24by means of which thethreadedends of the'rods are secured to the members 22.Y l The opposite -endsof the rods 23 `extend through openings in the members 19 in s uch al manner that4 the said mem' bers 19 are slidablygmountedon said rods. Each ofthe members 20 is'providedy with a set screw 20% for loc-king saidvmembers 19 .in their adjustedposition, and .provides means whereby. the members 17 may -be'movedtoward orfrom eah other to fit lawn mower frames of different dimensions.

The downwardly extending flange of each of the members 17 is provided with Ya T- shaped, slot 25.l Said'members 17 are designed to rest adjacent to the frame members 14 with the boltsl extendingthrough the slot 25.' This provides means whereby the frame members 17'may be adjusted toward or from the cutter blades 13. The outer ends of the members 17 are supported by'means of pivoted bars 26 which are provided with slots 27. Said Aslots 27 are each provided with a bolt 28 designed to extend through the opening of the bearing 16 from v which the: roller pins have been removed, and through the slotl 27 A thumb1 nut 29 is provided for locking the bar 26 adjacent tothe bearing 16. The pivoted bars 26, together with the bolts 15, provide means whereby the grinder 'frame may be rigidly connected to the vlawn mower frame.

Y. Slidably mounted on the guides 23 is, the

grinder frame which comprises substantially a channel bar 30 which extends transversely with the said guides 23, one end of the chan nel 30 being provided with a transversely arranged sleevel which 1s shdably mounted on the inner one of the rods 23. y The channel 30 is so constructed that it is slidably mounted on the shafts 23 and rotatively mounted thereon with its outer end'extending insideot theouter guide 23.

Secured to the bottom of theV channel 3() I have provided a plate 32 which is pivotally :member 32 and extends upwardly through an opening 37 inthe plate 34. A lever 38 is pivoted to the upper end -of the member 36 and has at its lower end la cam shaped portion 39 designed Ito engage'the upper surface of the plate 34 insueh a manner that as Y the lever 38 is rotated about its pivot, the

cam yportion 39 will engage the upper survfaceof 'the plate 341an'd elevate the plate`32 lto move its outer end toward and from the vunder surface Aof `the vrod 23. This provides means forvmoving ythe grinder hereinafter described toward and from-the cutter yblade 13'. i

The outerlend of the :bottom portion of the angle is provided with a set screw 40 fby meansof which the said outer end of the member 30 may be elevated-or lowered relative to lthe member 32. The spring 41 Iis provided for yieldably moving the member 30 toward `the member 32, the said Spring 41 being mounted on a `bolt 42 which is provided with a nut 43 for bearing the tension v'of the spring.

One of the upwardly extending flanges vof vthe members 30 is y'provided with a gear casing44 Whichis provided with a gear `45, an yintermediate gear 46 in mesh with the same anda pinion vgear 47 mounted on the ygrinder vshaft 48, oneend of which'extends into said gear casing. -Said grinder shaft is carried by a sleeve 49 which Aextends through the upwardly extending vflanges of the member n The shaft 48 has 'mounted o'nits outer end the grinder lwheel 50 by means of a threaded portion 5l on the grinder shaft and the plates 52 in the usual manner. The

V4gear 45 is mounted on a crank shaft 53 hav .inga crank V54 on one `end which is designed to be operated manually.

For sliding the grinder frame longitudinally ofthe guides '23, I have provided a rack bar 55, one end of which is ysecured to a plate 56 which in turn vislsecured to one of the members 22. rI`he rack bar 55 extends substantially parallel with` the rods 423 and ltransversely through `the lupright members of the channel 30. Said channel 3() is provided -with bearings '57 and 58 which are designed to receive -acrank shaft 597 the inner end vof which is provided. with a pinion 60 designed to coact with Ythe teeth of .the rack 55. The outer end of the shaft. 59 is ,provided wit-h a crank-6l which provides means whereby the grinder may be moved longitudinally of the guides 23. 'This is.

accomplishedv yby rotating said erank, which in turn will rotate the shaft 59 together withthe .gear GO, by means of which the grinder frame is moved relative to said guides.

Mounted on the forward end of the chanfnel 49 vis a cutter blade guide 62 which comprises an upright portion G3 which extends through an opening 64 inthe bottom of the member 30 yand is designed to `be `bolted adjacent tothe yinner face of one of 'the yupright flanges yof the Vmember 30by means of a bolt 65. rThe lower end of :the member '63 'is provided with a horizontally arranged portion K66 which khas a lnotch 167' running slightly angular with `the shaft v51. The notch 67 is designed to receive andIguide-'the blade 13, las clearly illust-rated in Figures 5 and G, so as'to retain the said blade in proper relation with the grinder 50.

It will be seen that i-fthe gri-nder Carriage is moved longitudinally of the guides, the

cutter 12vwi1l bel rotated so that the edge of the blade is always in cont-act` with the grinder J50 "during the entire movement of the carriage from one side of the 'cutter frame to the other.

In mounting the grinder frame7 I 'first rotate the cutter blades 13 relative'tothe vledger plate and mark any'such bla'des that engage the said ledger plate at their ends. I then-remove the ledger plate ,and also the supporting roller, after Vwhich I. clam-pythe rgrinder :in position Aas Abefore described.

which will cause the grinder tofbe Yelevated from the blade.V I then slide the carriage 'to the opposite side of the mower and adjust the gri-nder to the blades at said opposite end, and t-hen lockfthezgrinder frame in position. The vgrinder is lthen 'ready for tion. 1

vAfter moving the carriage to 'oneend the crank 6l is grasped and also 'the crank 54, the grinder being operated by the klast said crank and the carriage Vmovedlongitudinally of the guides with the crank 61.A All of the blades are ground in 'this manner', after which the carriage is again `moved to -the point of'rbeginning and the set screw 40 slightly adjusted tofmove the grinder closer to the 'blade in such Va manner that a new cut may rbe made. The -blades are again 'passed I then throw ,the Vupper Operathrough the grinder after which the grinder may be removed and the ledger plate and the roller replaced.

Thus it will be seen I have provided a grinder of simple, durable and inexpensive construction which may be easily and quickly attached, and which will accurately grind the blades ot a lawn mower.

I claim as my invention:

l. In a grinder for mowing machines comprising a supporting trame, means tor securing said trame to a lawn mower having a rotatively mounted cutter bar, a pair of guide bars in said frame arranged parallel with the axis of said cutter bar and in fixed relation therewith, a grinder 'frame pivotally and slidably mounted on one of said guide bars, a grinder mounted in said frame, said grinder being so located that when the said frame is adjusted about its pivot the grinder will be moved toward and from said cutter bar, a plate having one edge pivotally mounted to the inner edge of said grinder trame, a bearing plate slidably mounted on the other of said guide bars, means carried by said bearing plate for moving said first plate toward and from said second guide bar, the outer edge of said grinder Jframe being provided with a set screw designed to engage said lirst plate for adjusting said grinder trame relative to said iirst plate, and a spring for yieldably holding the outer end of said grinder frame inwardly toward said irst plate.

2. In a grinder for mowing machines comprising a supporting frame, means tor securing said trame to a mower having a rotary cutter blade, inner and outer guide bars supported in said frame parallel with the aXis of said cutter, a grinder trame pivotally and slidably mounted on the inner one of said guide bars, a grinder mounted in said trame, said grinder being mounted in such a manner that when the grinder frame is adjusted about its pivot the grinder member will be moved toward and from the cutter blade, a bearing plate on said outer guide bar, a second plate beneath said guide bars and said grinder frame, the inner edge of said second plate being pivotally connected to the inner edge of said grinder frame to allow a slight angular adjustment, a set screw for moving the outer end of said grinder trame outwardly from said second plate, a spring for yieldably moving the outer end of said grinder frame toward said second plate, and hand actuated means carried byA said bearing plate tor imparting movement to said second plate to thereby move said grinder trame to bring the grinder in contact with the cutter' blade, substantially as described and for the purposes stated.

3. In a grinder for mowing machines comprising a supporting frame, means for securing said frame to a mower having a rotary cutter blade, inner and outer guide bars supported in said frame parallel with the aXis of said cutter, a grinder trame pivotally and slidably mounted on the inner one ot said guide bars, a grinder mounted in said frame, said grinder being mounted in such a manner that when the grinder :trame is adjusted about its pivot the grinder member will be loved toward and' 'from the cutter blade, a bearing plate on said outer guide bar, a second plate beneath said guide bars and said grinder frame, the inner edge of said second plate being pivotally connected to the inner edge of said grinder frame to allow a slight angular adjustment, a set screw for moving the outer end ot' said grinder trame outwardly from said second plate, a spring tor yieldably moving the outer end of said grinder frame toward said second plate, hand actuated means carried by said bearing plate for rotating said second plate to thereby move said grinder l'rame to bring the grinder in contact with the cutter blade, means for imparting movement to said grinder, and means for moving said grinder traine longitudinally' of said guide bars.

Des Moines, Iowa, April 20, 1925.

PHILIP A. ANDERSON. 

